A crack may appear on the wall of the house at any time, and the owners of the building immediately wonder how dangerous this phenomenon is. Experts distinguish between two types of cracks - passive and active. And if in the first case the defect in question can be "removed" with your own hands, then in the second you will have to involve professionals in the work. But first you need to understand what factors provoke the appearance of cracks.
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Causes of cracks in the house
It is believed that in the first five years after the construction of a house, cracks appear on the walls in 90% of cases - experts call this natural shrinkage, which does not pose any danger. But it also happens - the house has been for many years, it is quite habitable, all structures are regularly repaired, but cracks still appeared. What is the reason for this phenomenon?
Firstly, cracks in the house may appear due to violations in the technology of erecting the walls themselves. For example, if the dressing of brickwork was carried out incorrectly.
Secondly, the phenomenon under consideration on the walls of the house may be caused by non-compliance with the sequence of construction work. For example, communication systems (water supply, sewerage) are often carried out after the construction of a house - you have to dig out the foundation, which negatively affects its quality characteristics.
Thirdly, foundation settling often occurs - for example, due to compression of the foundation soils or too much pressure of the house on the foundation. This is possible if the construction of the foundation was carried out without preliminary calculations and design. The most common mistakes:
- during the construction of the foundation, geodetic surveys were not carried out, the nature of the soil was not studied;
- the ground resistance taken as a basis was erroneous, greatly overestimated;
- geodetic surveys at the construction site were carried out in the summer - the level of groundwater rise was not calculated;
- a mistake was made when choosing the type of foundation - for example, a linear one was laid instead of a columnar one;
- no calculations were made of the depth of the foundation of the foundation, its thickness - usually these parameters are based on data on past construction sites;
- violations of the technology of laying a sand cushion under the foundation - for example, insufficient layer thickness or poor-quality compaction of sand.
Note:cracks in an old building can also occur due to structural changes in the building. Often, owners will set up a subfloor in a non-intended foundation, and the result will be displacement / shrinkage of the foundation base.
When even a small crack is found, the main question arises - is it dangerous? It is quite simple to check this - you need to install a control beacon and observe the "behavior" of the crack for a long time. Professionals put such control beacons special - plate, which must be registered with the supervisory authorities. At home, with an independent solution to the problem, you can use one of the following methods:
- stick a strip of paper on the crack with the date of installation;
- prepare a plaster mortar and put a strip of it on the crack.
And then all that remains is to wait and periodically check the status of the control beacon. It may take several months before any conclusions can be drawn - experts say that it is necessary to control the crack for 8-12 months.
How dangerous it is, the rupture of the control beacon will show - if there is such a phenomenon, then it will be necessary to apply complex technical solutions to eliminate the problem, if there is no rupture in the beacon, then there is no need to worry at all.
Methods for eliminating cracks in the house
Different cracks are fixed in certain ways - you need to first determine the level of the problem.
Note:if the control beacon showed a rapidly expanding crack, then no way to eliminate the cracks with your own hands will help - they will only have a short-term effect. Be sure to invite specialists to solve the problem, otherwise the consequences will be the most terrible - the collapse of the wall or the entire structure!
How to fix a crack in a house from the inside
If small cracks are found on the wall inside the house, then fixing them is as easy as shelling pears. You only need a primer and a special putty mesh. You need to act according to the instructions below:
- we clean the surface of building materials, finishes - the wall should turn out to be perfectly clean;
- we use a deep penetration primer (with this marking!) - cover the entire cleaned surface;
- we glue the putty mesh on the entire prepared surface;
Note:It is necessary to cover the entire area of damage on the wall with a special mesh - even small sections of cracks should not protrude beyond its limits.
- Apply a small layer of putty to the mesh and leave it to dry completely.
Only after the putty layer has completely dried can you start grouting the surface and gluing wallpaper or other finishing materials.
Elimination of a crack in the house from the outside of the wall
If small cracks appear outside the house, you should proceed according to the same principle as in the above option. Procedure:
- the crack is cleaned from plaster or debris;
- apply a layer of deep penetration primer and putty mesh on it with glue;
- put putty on. But! In the case of eliminating the cracks on the outer walls, it is advisable to use a special reinforced putty - it is resistant to the negative effects of atmospheric changes.
If the cracks on the outside of the walls of the house have gone not only through the plaster, but also spread to the brickwork, then much more effort will have to be made. And in this case, the algorithm of actions will be as follows:
Note:the metal mesh must cover the entire surface intended for the application of the new layer of plaster. Thus, the new plaster will not blur, which will allow the finishing materials to be applied flawlessly.
This situation means only one thing - it is urgent to take drastic measures to eliminate such a problem. If you ignore all the recommendations of specialists, limit yourself only to the above repair options, then the result will be the collapse of the whole house. But a beginner can also cope with the work of eliminating such complex active cracks - the main thing is to strictly adhere to the following instructions:
- All the plaster from the wall at the location of the crack gets lost - be sure to maintain a distance of 50 cm on each side of the crack.
- The crack is cleaned of mortar and dirt - this can be done with a metal spatula.
- The cleaned crack is filled with polyurethane foam.
- Fastening metal plates that will tighten the crack, preventing it from spreading further. In this case, it is necessary to take into account the following points:
- the plate must be chosen from thick, high-quality metal;
- to obtain an optimal result, you will need to tighten the crack with at least 3 plates, and if the crack is long, then 4 or 5 metal plates may be needed;
- plates are attached using self-tapping screws, but using dowels.
After applying the fastening metal plates, you can continue to work according to the usual algorithm - priming / fixing the reinforcing mesh / applying new plaster.
But keep in mind - such events serve as a temporary measure, since without a specific education it will not be possible to determine the cause of the appearance of active cracks. Most often, in the future, it will be necessary to carry out correction work on the foundation - it is either strengthened / strengthened, or the walls / roof of the house are raised and the base is completely replaced.
Prevention of cracks in the house
In order not to have to deal with cracks in the house, it is worth familiarizing yourself with the prevention of such a phenomenon.
Firstly, if only a house is being designed, several points must be taken into account.:
- carrying out geodetic surveys must be completed - this will help determine the type of soil, the location of the aquifers, the depth of the water soils;
- even at the stage of drafting the project, it is necessary to provide for the possibility of building an underground / cellar under the house - this will entail serious structural changes;
- it is imperative to familiarize yourself with the depth of soil freezing - the depth of the foundation will depend on this.
Secondly, when buying an old house, pay attention to the existing walls, invite specialists to assess their condition - often serious problems in the stability / reliability of the entire structure are hidden behind the small size of the cracks. One more point - there should be a blind area around the whole house - this will prevent moisture from entering the foundation, and therefore, will serve as a prevention of its destruction.
Obeying the latest design trends, most owners of private houses and cottages opt for brickwork when decorating buildings. Such a coating provides buildings with an excellent view, and also serves as a protective, decorative and cladding material. In terms of its strength characteristics, facing brick surpasses many finishing options, therefore in our country it is especially in demand, even if the cost of the material and laying work is high. However, in order to maintain durability, the coating needs maintenance in order to avoid such a phenomenon as cracks in the facing brick.
Reasons for the appearance of cracks in facing masonry
Even with strict adherence to the rules for building a house, there is a likelihood of unpleasant situations in the form of shrinkage and thermal deformation of coatings. They are also the main causes of cracks in the brick facing surface. Deformation can lead to various phenomena:
- to shrinkage due to exposure to moisture, due to which there is a decrease in volume, compaction and hardening of the facing coating;
- to a change in linear dimensions during thermal compression and expansion.
The shrinkage process is natural and usually occurs over several years. But the temperature deformation is mainly influenced by the change of the season, daily temperature fluctuations, the position of the lined walls in relation to the cardinal points. Note that the front surfaces of the walls located on the sunny side of the house are more prone to linear expansion. You can prevent these phenomena by following a few simple rules.
How to prevent cracks in brick cladding: 7 professional tips
Given the likelihood of linear brick shrinkage and periodic temperature fluctuations, it is possible to prevent the formation of cracks in the building cladding by adhering to the following rules:
- Dry the facing products as much as possible before laying them on the main surface.
- Strictly follow the masonry methodology based on the arrangement of the so-called stitch rows. The method involves laying butt rows of solid elements in places such as the upper and lower rows of the structure being erected, in belts and cornices, under beams, girders and bearing plates, as well as every four spoon rows. In addition, the facing masonry must be tied up with anchors and unloading belts must be used.
- In the process of facing masonry, use a reinforcing steel mesh with a diameter of 2-3 mm. Such a mesh will reduce the deformation load on the facing surface, thereby contributing to the long-term preservation of its integrity.
- To equip expansion joints over the entire masonry surface, which in the facing will simultaneously perform the functions of both shrinkage and expansion joints. Their thickness should not exceed 15 mm.
- Avoid getting moisture on the facing brick during its transportation, processing and laying.
- Avoid freezing and thawing of the walls of the building.
- Carry out the facing masonry using the most rigid mortar, plasticizers and non-shrinking additives in order to avoid getting the products wet and in order to prevent cracks during the drying process of the facing surface.
Although cracks in the facing brick coating do not affect the bearing capacity of the masonry, they nevertheless spoil its appearance.
How to extend the life of facing brick masonry
To extend the life of the brick cladding of your home and to identify possible cracks in time, the first thing to do is to inspect the cladding in order to identify and further eliminate defects. At this stage, not only the outer walls of the building are carefully checked, but also the masonry seams. All chips and cracks in the facing brick are sealed with a special sealant, which is matched to the color shade of the base material. For the joints, as a rule, mortars similar to those used in the production of masonry are used - so the restored sections of the facing masonry will not stand out from the overall architectural composition.
The next stage involves cleaning the brickwork from dirt and dust, while experts do not recommend using the wet method for this. It is best to wipe the surface with a soft, dry cloth to prevent moisture from entering the brickwork.
To ensure optimal protection of facing brickwork at the finishing stage, it is recommended to apply an additional protective layer - this can be a special varnish, water repellents or clinker oil. These types of coatings will well save the cladding of your home from negative factors for a long time. Even after becoming unusable, lacquer and coloring compounds are much easier to remove and cheaper to reapply than to restore the brickwork itself. At the same time, the well-groomed appearance of the building will continue to delight the eyes of its owner.
Brick is one of the most popular materials for the construction of various objects. However, this material is not ideal, and flaws and damage can occur in buildings made of it during their operation.
The most common flaw is wall cracks. Correcting such a flaw will not be difficult. To do this, you need to find out the cause of the crack and select the necessary technological method to eliminate it.
Peculiarities
Cracking on brick wall surfaces is a bad sign. However, with a correctly laid foundation and correct masonry, cracks should not occur.
Any visible flaw signals non-compliance with the norms of construction or use and needs to be immediately corrected for the cause of its appearance. The level of difficulty in sealing cracks in wall surfaces depends on their thickness and depth (sometimes you have to disassemble the required area of the brickwork).
You can fill the crack with your own hands if you follow our recommendations. We will help you fix any imperfections (eg cracked surface of a load-bearing wall).
Causes of cracks
There are several reasons for this frustrating problem.
- The absence or inadequacy of the link between the blocks. It manifests itself in the form of a vertical crack along the entire height of the wall (occurs during the construction of an extension to an existing building or if the correctness of the work is not observed). You can get rid of the gap only if a preliminary screed is made with a reinforced belt.
- Disadvantages when laying the foundation of the building: pouring the foundation to a shallow depth (less than the level of soil freezing), the use of granular or mineral blocks, the use of concrete with poor strength and resistance to frost. External manifestations: crevices in corners or rapidly growing cracks in the tops of brick wall surfaces.
This can be avoided by strengthening the perimeter of the foundation by creating a belt of concrete.
- Erroneous determination of soil quality, due to which errors occur when taking into account the load. This also includes soil deformation due to vibrations, natural phenomena (such as active groundwater), as well as work performed in the vicinity of the site. All this leads to the appearance of large cracks along the entire surface of the walls.
- Settlement of the structure during the first year of operation. This manifests itself in the form of small and shallow gaps, which do not further increase in size. To eliminate them, only minor repairs need to be made. ... Cracks occur in areas of greatest stress. To avoid this, you need to distribute the load evenly and make a screed in the necessary places.
In order to close a crack in the wall of a brick house, you should follow a simple instruction:
- carefully inspect the entire building, recognize and eliminate cracks;
- periodically check the condition of wall surfaces;
- if the slightest cracks are found, everything possible should be done immediately to prevent the spread of defects;
- when cracks form, it is necessary to clear the necessary inner area of the cracks, as well as to maximize the interaction with finishing agents;
- after checking the walls and processing the cracks, the detected cavities should be covered and the outer insulation (or decoration) should be made.
Until the cause of the flaw has been identified, it is pointless to do anything to fix it.
In addition, it is necessary to continuously check the rate of crack growth. For this, the gap must be marked with markings from a putty composition or concrete mortar. Desired strip dimensions are 100x40mm with a layer thickness of less than ten millimeters. There is also an easier method using paper. Check for breaks every day for five weeks. If problems arise, a major overhaul of the base of the structure and the help of a professional are required.
It is worth remembering that a crack width of more than twenty millimeters is critical. In such a situation, additional strengthening of the edges of the cracks and strengthening of brick structures is necessary. Destructive areas need to be dismantled.
If, after checking, you notice that the crack has not increased, then you can use a simple method to seal the gap in the brick wall.
Crack fixation methods
It is worth remembering that the occurrence of vertical crevices with a width of ten millimeters or more is a harbinger of the destruction of the walls of the structure. Therefore, it will not be possible to repair this crack with cement mortar without a strong metal screed. In this regard, there are several repair options.
- Driving in special anchors made of metal into dowels mounted on the edges of the crack.
- Installation of longitudinal metal brackets with bends at the edges into pre-made holes in wall surfaces (later they should be covered with cement mortar). This method is the easiest and most reliable when correcting through cracks from the outside.
- Reinforcement of brickwork from the inside with special fastening joints. When mounting fasteners into the wall surface, they must be recessed to a great depth (more than half of the entire wall thickness). It is quite possible to alternate fasteners. In practice, the filling of gaps in brick wall surfaces is carried out after the installation of the fixing structures.
- Using reinforcement mesh it is rational, if desired, to strengthen the entire area of the structure, because even a careful calculation of the foundation does not guarantee the absence of the risk of shrinkage. When choosing a method and material for eliminating cracks, it is necessary to take into account the forthcoming exterior finish. All parts made of metal material are treated with anti-corrosion compounds and masked by painting or plastered over with plaster.
How to repair cracks
Compositions for sealing gaps depend on the location of the flaws (from the inside, outside the house, or even under the window). Inside the room, it is possible to tighten the crack with a gypsum-based composition or a mixture of lime and cement. For outdoor installation, it is better to choose the materials that are most resistant to moisture (otherwise, the finish will not last long).
- For minor cracks(less than five millimeters wide) repair with cement mortar is suitable. In situations where shrinkage microscopic cracking does not exceed one millimeter, it is better to cover them with epoxy resin.
- For defects with a length of five to ten millimeters the filling can be done with a mixture of cement and sand in a ratio of 1: 2 or 1: 3. To achieve a plastic consistency, add water.
- For more problematic cracks in brick wall structures (as well as in structures with an air layer), foam for installation will be an excellent solution. Such material requires mandatory protection from sunlight, therefore, after hardening, the foaming excess is removed.
- For defects of various types a cement composition with the addition of polymers from the category of M400 grades is suitable. The compositions are passed through a fine grate with medium-sized grains of sand or wood glue based on polyvinyl acetate and water. PVA in such cases is added in excess (from one liter per bucket) and added to the composition last.
- For problem areas of the wall(inside or outside), you can use a silicone based sealant. The advantages of such a tool include plasticity and a long service life of the material, tolerance to changes in temperature and humidity, and the convenience of sealing cracks with an assembly gun. The disadvantage of this method is large financial costs, so it is not suitable for large areas and volumes.
- If it is necessary to eliminate defects from the outside and in the presence of an outdated solution, mixtures with the addition of brick crumbs are used.
At the end of the repair, the condition of the brick surfaces must be carefully inspected within two months.
Good day! The house is 2 years from the date of construction.
Foundation:
Reinforced monolithic tape (3 rows of 3 rods of 14 reinforcement, vertical rods every 1.5 meters) laid to a depth of 1.5 m, tape width 50 cm. drains are diverted several meters from the house). No vertical waterproofing was done. There is no drainage due to the complexity of the organization and the inability to drain water (a house within the city, dense buildings).
The foundation was laid on the site of the old house with the complete removal of the previous foundation (there was a shallow tape), there were no cellars. There was a toilet 2.5 meters deep - it was filled up and tamped down, it was located at the northeastern corner of the present house.
Soil: 20-50 cm fertile layer, then 3-5 meters of water-saturated loam and clay. The peculiarity of the soil is that due to poor water permeability, loams are saturated with water for most of the year. Mirror of water in a well is from 20-50 cm in spring, up to 2.5-3 meters at the end of dry summer. In "normal" weather - 1.5 meters from the ground level. The plot after the construction of the house is raised by about 50 cm to the level of the neighbors.
Plinth: 4 rows of hollow silicate bricks. Horizontal waterproofing was made between the tape and the plinth and between the plinth and the bearing walls (two layers of roofing material).
Walls - "well" masonry. The main walls are made of autoclaved gas silicate D600, then 5 cm of insulation (penoplex), a minimum ventilation gap, then a facade in half a silicate brick. The connection between the wall and the cladding is a continuous welded mesh of 1.5 mm every three rows of gas silicate. Walls, insulation, cladding are fully supported by the base.
House on two floors. Armo-belts were made between the first and second floors and between the second floor and the roof.
The lintels above the windows and openings for the main walls are made of factory-made reinforced concrete lintels (lintels are 50-60 cm wider than the openings, the support points are reinforced with silicate bricks). The lintels on the cladding are made using a metal corner with a width of 10x10 with a thickness of 1 cm, the corners are also wider than the openings by 50-60 cm.
I noticed a crack under a wide window on the east side of the house. The crack extends from the window through 4 rows of bricks vertically, then shifts slightly to the veranda (3 more rows), closes before reaching the base of 3 rows (see fig, crack under the widest window and its direction is shown in red). It is noticeable that it opens slightly from above (up to 1 mm).
Immediately after construction, a similar crack appeared under a narrower window on the south side (see Fig.) - it also goes through several rows. However, the crack on the south side looks more like an expansion joint - when the wall heats up, it completely closes, and in cold weather it is slightly open (~ 1 mm).
A new crack under a wide window is not like a crack under a narrow window. The main difference is that it has a distinct disclosure. I have been observing the crack for several days and so far I have noticed only the dynamics of its increase. Lighthouses are tearing. It does not depend on the air temperature. I examined the basement from the inside - I noticed hairline cracks on the bricks approximately in the area of the crack under the window. There are no cracks on the foundation.
Please tell me whether to worry or not? What can be done to determine the cause of the crack and fix it ...
A common problem is cracks in a brick house, which arise for various reasons. Correct sealing of cracks in brick walls allows not only to externally cover up the cracked area on the wall, but also prevent the problem from recurring. A gap can form on the load-bearing wall, which is most dangerous, especially in a multi-storey building.
Why do they arise: the main reasons
If a brick wall is cracked, then you need to find out what are the sources of the violation. Often, brickwork cracks on the front side, which may be due to an incorrectly selected mortar or decorative tiles, disrupted work technology when facing the facade of a building. Cracked brick walls on the outside are often attributed to variable climatic conditions, in which severe frosts are replaced by hot days, as a result of which the foundation cannot withstand.
If the horizontal or vertical cracks in the brickwork are not repaired in time and correctly, the entire structure may collapse.
Permanent sources
If a load-bearing brick wall has burst, then the reason may lie in the improper shrinkage of a multi-storey building, which is associated with different pressures on the foundation at the corners of the building. This happens in situations where one wall is completely deaf from silicate bricks, and the second is glazed. There are other permanent factors that affect the appearance of cracks:
A defect in the wall can appear when the house is located close to the highway, along which heavy vehicles often drive.
- External influence, in which water is pumped out, pits are dug and other manipulations are performed, leading to the subsidence of the foundation.
- The specific influence of heaving type soil. When it freezes, an uneven rise is noted, and when thawing, the foundation shrinks unevenly on all sides.
- Mechanical factors. When the amount of reinforcement decreases or there are no expansion joints and gaps, the masonry or facing brick cracks.
- Dynamic type impacts. These include the work of technical equipment, which is carried out near multi-storey buildings. It is also possible that cracks appear in the brick walls when the highway is located nearby, along which heavy vehicles regularly move.
Temporary
The appearance of such cracks in a brick house is associated with the influence of such factors:
- natural deformation processes during construction shrinkage at the end of construction;
- live load on the surface located next to the dwelling;
- deviations in the construction of walls, for example, when connecting an old and a new building, in which the brickwork is incorrectly performed;
- brick wear during prolonged use due to high humidity.
How dangerous is it?
To track the dynamics of the crack, controllers are glued to it.
If a multi-storey building burst and the repair work was not carried out on time, then the crack is dangerous with a large discrepancy. To determine the level of danger, it is necessary to position the control latch, observing the condition of the seam. If you yourself find it difficult to deal with the problem of damage to brick walls, then call the master. The specialist has special plate-type beacons that are registered with the supervisory authorities. If it is impossible to call the wizard, perform the following actions:
- In the place where the brick bursts, a paper strip is glued, indicating the date of its fixation.
- A small horizontal strip is made with a cement mortar over the crack that has appeared.
Check the status of the control beacon regularly. Sometimes it remains unchanged even after 2-3 months. It takes a year on average to fully assess the condition of a brick wall. How dangerous the crack shows damage to the controller. When it breaks, it is necessary to pull off the walls of a brick house using technical solutions.
If the control beacon remains unharmed, then there is no need to worry and it will be enough just to hide the defect by covering it with plaster along the resulting seams.
Elimination of external cracks
Such types of damage in masonry occur quite often and require the following actions:
Reinforced mesh is used to fix the outer crack.
- The place where the brick is cracked is thoroughly cleaned of plaster and dirt.
- Primer the wall with deep penetration mortar and glue the filler mesh.
- Apply a special reinforced putty for external work. When choosing a conventional material, the crack may soon reappear after several weathering.
If deep cracks have gone not only on the facing brick, but also on the masonry, then more radical measures are required. Sometimes it is required to reinforce the foundation with reinforcement. Major elimination of cracks in brick walls is carried out as follows:
- All plaster is cleaned and a special metal mesh is attached, which is fixed with bolts.
- A solution of cement and sand is applied over the mesh, while the plaster layer should be like the previous one, so that there are no drops.